Build and run a closed-loop life support system that supports two people for a set time. At the end of time, the system must be in the same state as the beginning ('steady state'). When the first life support challenge is won, the next challenges will be progressively more difficult (support more people over a longer time) with larger prizes.

That may be a good idea - I repeatedly have in mind a system of caves detected in Romania a few years ago. The system has been disclosed from the our normal environment totally for 25.000 years under the surface - and is full of life and sufficient water and food supply. The animals all were insects up to scorpions without any eyes because there were not light in the caves.

So I am supporting your idea but propose to begin a little bit smaller at the level of insects. That would be easier, cheaper... - and easyly done by private space travel firms perhaps.

There is at least one problem such systems could solve once there would be success - providing food etc. during space missions and on other planets having no ecology.

There is at least one closed loop system running - the earthian ecology as a whole.

There is at least one ecology very much easier to inspect than the earthian ecology - the system of caves detected in romania. This ecology is much less complex than the earthian system.

This romanian system might have connections to the atmosphere concering oxygen, nitrogen and carbondioxyde but not much more. An additional element will be the rocks it has been surrounded by. These rocks might be researched easyly because they are not as complex as the ecology they are surrounding.

From this new insights useful to establish artificial ecologies for space might result.

the discussion should go on I think - we can work it further here and it would be something private space travels might work on and might have use from.

I say this because I realized this moment that there are different classes of such systems:

1. Systems stable and not to much degenerating for a given period of time.
2. Systems stable for ever.
3. Systems connected periodically to other systems to remove instabilities and regenerations.

idiom, did you happen to be in error saying "regenerative" instead of "degenerative"?

Concerning 3. I'm thinking of the fact that earthian land repeatedly is improved chemically or biologically by the farmers.

Why not doing this with the proposed systems too when they are in earthian orbit - for ever or arriving from other planets - or in an orbit of a planet where the required chemicals or biological ingredients are sufficiently available too?

This modification would mean that the proposal itself no longer would be a closed loop system - but it would extend the arthian closed loop system to space and other planets. And this ,ight be much more efficient and useful than the original idea. It really would be the beginning of a solar-system-wide ecology.

And it could include physical-chemical parts very well too. I'm known to a botanist who told me that for life not light and water are required but energy and fluidables. There is much energy in space and the cold of the space causes gases to be fluidables that might substitute water. Additionaly plants are considered to be possible that are resistable to radiation - they may form a useful part of ecological systems in space or other planets.

All this can be a good job for private orbital stations - especially if fodd etc. for orbital tourists is to be provided.

Biosphere 2 was an ambitious attempt at a large mostly-biological life support system.

In hindsight, it would have been better to create 10 small life support systems, each using different methods, rather than one big life support system using one method. A challenge involving life support systems would achieve this.

You went to Biosphere 2 a couple of times. What's your sense of the value of that rather extravagant enterprise?

I was very enthusiastic about it. My first visit happened before they went in - when they were doing small-scale enclosure experiments, which I found more interesting than the big one. It would have been much more valuable to have had five or six small ones. You could find out what went wrong more rapidly and try out different approaches. Having just one is not good science.

As a work of art, it was great - the little rain forest, the lake, the farm, and various other ecological units. As a piece of science, it wasn't well designed. The second time I went, they were enclosed. All I could do was put my hands against the glass and exchange greetings on the telephone. But it seemed to be going quite well. Then they had a calamity, which was very satisfying to me - the fact that things turned out to behave in unexpected ways. The press castigated them because they ran out of air, but, to my mind, that meant it was good science because you found out something new.

Even the scientific press - until last year in Science magazine - said it was bad science, irrelevant, a blot on the escutcheon of science. You don't view it that way?

Biosphere 2 was much more than science; it was a human adventure. It was like the Apollo program, which wasn't really science either, but it had huge excitement attached to it and was a great sporting event. The science was simply an extra dividend.

Say something about failure in experiments or businesses or anything else. What's the value of failure?

You can't possibly get a good technology going without an enormous number of failures. It's a universal rule. If you look at bicycles, there were thousands of weird models built and tried before they found the one that really worked. You could never design a bicycle theoretically. Even now, after we've been building them for 100 years, it's very difficult to understand just why a bicycle works - it's even difficult to formulate it as a mathematical problem. But just by trial and error, we found out how to do it, and the error was essential. The same is true of airplanes.

This brings up an interesting issue of where theory fits in. Presumably there was not a theory of planes before there were planes.

There was an attempt at a theory of airplanes, but it was completely misleading. The Wright brothers, in fact, did much better without it.

So you're saying just go ahead and try stuff and you'll sort out the right way.

That's what nature did. And it's almost always true in technology. That's why computers never really took off until they built them small.

Why is small good?

Because it's cheaper and faster, and you can make many more. Speed is the most important thing - to be able to try something out on a small scale quickly.

Fail fast.

Yes. These big projects are guaranteed to fail because you never have time to fix everything.

Your idea of a solar system ecology is very interesting, but I have a different view.

I prefer many small ecologies rather than one big ecology because multiple systems are tougher and more likely to succeed in the long term. If the big ecology fails, there is no alternative or backup. But if a small ecology fails, then it's no big deal because the rest are still there.

I don't intend to creat this solar-system-wide ecology as a whole system - I think of ot as a possible result of the multiple systems. This is because several of the multiple systems will be providing several new insights and advantages as a basis to create an additional new system or - in other words - to remove errors made in others of the multiple systems.

So I don't want a system-wide ecology as once - it's a vision of a later evolutionary step.

But there's a distant analogy to what I said in my earlier post - before man began travels to other continents the american ecology to a very high degree was disclosed from the eurasian-african ecology and from the australian ecology. And the latter two were disclosed from another too. Only after travels by ship and trade were established the ecologies began to mix.

Your proposal(s) and the quoted interview are concerning such disclosed ecologies. So there are experiences since hundreds of years that perhaps could be applied.

And within the continents there are ecologies disclosed too but by a lower degree.

Dipl.-Volkswirt (bdvb) Augustin (Political Economist)

EDIT: And there is another possibility to be added - computer simulations. The technology seems to be available already and think of the games concerning th evolution of populations and civilisations. The crew of a spaceship providing its own ecology or a colony might wish to observe and control this ecology and use measurements to prevent insane evolutions - the simulations might help them.

The real problem is that a true closed-loop biosphere is very very hard and it's even worse in space. In space, you can have outgassing that you don't get on Earth.

Besides, it can probably be done incrementally. Right now, you can do pretty well where the food and water is shipped in from earth. Your excreted water is used to make oxygen (the hydrogen is dumped overboard), the CO2 is dumped overboard, and there are periodic nitrogen shipments to make up for outgassing. That's "good enough" for a low-earth-orbit station.

Want to make it more independent? Start adding plants. Eventually, the plants will start to replace large sections of the food and water shipments (the water's not strictly necessary anyways, it's just a tad creepy to drink what you know is very corsely filtered urine), less CO2 and hydrogen is dumped overboard, and you are mostly shipping up far less food (i.e. meat) and nitrogen. Add some fish and rabbits, and you ship up even less food.

You'll still end up needing at least some input, unless you've managed to successfully teraform a whole planet, however.

I think it's probably better to do it in stages anyway. It's much less momentus occurance, but it's much safer. You still have some of the non-regenerative systems around in case you guess wrong or there's wide-scale crop failure or a space-radiation-mutated trout pandemic or something.

The problem is, it's going to be a long time before we really need a closed-loop life support system. Even a space hotel will be able to get along just fine without one -- and it's probably better for a hotel to have caviar, filet mignon, and such available...

On earth small experimental closed loop systems perhaps might be created and worked on by seriously interested hobbyists - I'm thinking about people being members of organizations like the "Schrebergarten"-clubs in german cities and towns and especially those of them interested in ecology and biology in scientific sense or being scientists for example.

Additionally people having a terrarium, a paludarium or an aquarium might be interested. They may be addressed by their journals.

Concerning the systems themselves besides plants and insects fishes might be a possible part of them - and fish is said to be healthy.

Closed loop life support systems with small organisms would be a good alternative to traditional terrariums and aquariums: and there's no maintenance!

I've seen two companies on the internet that sell such items: EcoSphere and Beachworld. There could be more.

EcoSphere was developed by Joe Hanson of NASA's Jet Propulsion Laboratory.

Carl Sagan wrote this essay about the Ecosphere: The World that Came in the Mail:
"The world arrived in the mail. It was marked "Fragile." A picture of a cracked goblet was on the package. I unwrapped it carefully, dreading the discovery of a shard of glass or the tinkle of broken crystal. But it was intact. With both hands, I lifted it out and held it up to the sunlight. It was a transparent sphere, about half filled with water... The number 4210 was inconspicuously taped to it. World number 4210: There must be many such worlds. Cautiously, I placed it on the accompanying Lucite stand and peered in..."